pcl_grid_min: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/pcl_grid_min - from package: pcl-tools

You may install the required package with command apt-get install {package}

Error in other languages:
pcl_grid_min: bevel nie gevind nie
pcl_grid_min: comandă negăsită
pcl_grid_min: comando não encontrado
pcl_grid_min: commande introuvable
pcl_grid_min: command not found
pcl_grid_min: käsku ei ole
pcl_grid_min: không tìm thấy lệnh
pcl_grid_min: komanda nerasta
pcl_grid_min: Kommando nicht gefunden.
pcl_grid_min: kommandot finns inte
pcl_grid_min: komut yok
pcl_grid_min: nie znaleziono polecenia
pcl_grid_min: níor aimsíodh an t-ordú
pcl_grid_min: no se encontró la orden
pcl_grid_min: no s'ha trobat l'ordre
pcl_grid_min: opdracht niet gevonden
pcl_grid_min: parancs nem található
pcl_grid_min: perintah tidak ditemukan
pcl_grid_min: príkaz nenájdený
pcl_grid_min: příkaz nenalezen
pcl_grid_min: команда не найдена
pcl_grid_min: командата не е открита
pcl_grid_min: 命令找不到
pcl_grid_min: コマンドが見つかりません